1. Field of the Invention
This invention relates to formation of memory devices and more particularly to a method of forming a split-gate EPROM, flash memory device having a floating gate electrode with a sharp polysilicon peak.
2. Description of Related Art
U.S. Pat. No. 5,445,999 of Thakur et al. for "Advanced Technique to Improve the Bonding Arrangement on Silicon Surfaces to Promote Uniform Nitridation" describes formation of a native oxide layer on a substrate with silicon molecular clusters. Radiant energy is used in the presence of a reactive gas to convert silicon molecular clusters and already dangling bonds into a uniform dangling bond configuration on a silicon or polysilicon substrate.
U.S. Pat. No. 5,492,854 of Ando for "A Method of Forming a Semiconductor Device" describes a process including forming a capacitor with a lower electrode composed of polysilicon. The device is heated in an atmosphere containing a SiH.sub.4 gas to remove a native oxide film on a surface of the lower electrode. Then a silicon nitride film is formed in an atmosphere excluding oxygen.
U.S. Pat. No. 5,614,747 of Ahn et al. for "Method for Manufacturing a Flash EEPROM Cell" describes forming a floating gate structure.